Chapter 5 - Workbook

Question 1

What are protein threads that compose myofibrils called?

Answer 1

Muscle filament

Question 2

Circular muscles that surround the eyelids are called what?

Answer 2

Oricularis oculi

Question 3

What happens when actin and myosin filaments slide past each other?

Answer 3

Muscle contraction

Question 4

A muscle that contracts to produce a particular action is called what?

Answer 4

Agonist

Question 5

What are inward extensions of the plasma membrane that surround myofibrils called?

Answer 5

Transverse tubules

Question 6

When a motor nerve is disconnected from a muscle, the muscle loses tone and becomes what?

Answer 6

Flaccid

Question 7

What is the attachment of the muscle to the more movable bone called?

Answer 7

Insertion

Question 8

Depolarization may cause an electrical impulse to be generated in the muscle fibre which travels across the plasma membrane and spread through the T tubules. What is the electrical impulse called?

Answer 8

Action potential

Question 9

What is a contractile protein that forms thick filaments called?

Answer 9

Myosin

Question 10

The trapezius extends what?

Answer 10

The head and neck

Question 11

What is the basic unit of muscle made of actin and myosin filaments?

Answer 11

Sarcomere

Question 12

What are interwoven filaments that join sarcomeres at their ends called?

Answer 12

Z line

Question 13

What is a contraction in which muscle tension increases, but muscle length does not change called?

Answer 13

Isometric

Question 14

What is a muscle that produces the opposite movement to an agonist called?

Answer 14

Antagonist

Question 15

Skeletal muscles produce movement by pulling on these, which pull on the bones. What are these?

Answer 15

Tendons

Question 16

What is the connective tissue that wraps a fascicle called?

Answer 16

Perimysium

Question 17

What is a cross-bridge?

Answer 17

Links actin and myosin filaments

Question 18

What are the cells that make up each skeletal muscle called?

Answer 18

Muscle fibres

Question 19

What is a bundle of muscle fibres called?

Answer 19

Fascicle

Question 20

What is the connective tissue that covers a muscle called?

Answer 20

Epimysium

Question 21

Which neurotransmitter is released into the synaptic cleft between the motor neuron and the muscle fibre?

Answer 21

Acetylcholine

Question 22

When additional energy is required, what is stored in muscle cells that is degraded to yield glucose?

Answer 22

Glycogen

Question 23

What is a junction between neurons or between a neuron and an effector?

Answer 23

Synapses

Question 24

A contraction in which muscle shortens and thickens as it contracts while the muscle tone remains the same is called what?

Answer 24

Isotonic

Question 25

The deltoid abducts what?

Answer 25

The upper arm

Question 26

Depolarization of the T tubules triggers the release of what stored ion?

Answer 26

Calcium

Question 27

Muscles maintain a state of partial contraction called what?

Answer 27

Muscle tone

Question 28

What muscle flexes and adducts the leg?

Answer 28

Sartorius

Question 29

What is a contractile protein that forms thin filaments called?

Answer 29

Actin

Question 30

Muscle fibres stockpile something, which can transfer its stored energy to ATP as needed. What is the something?

Answer 30

Creatine Phosphate

Question 31

Release of inorganic phosphate from the myosin causes what?

Answer 31

Cross-bridges to flex

Question 32

What is another name for a prime mover?

Answer 32

Agonist

Question 33

In depolarization, calcium ions bind to the proteins on what?

Answer 33

Actin filament

Question 34

Which two muscles raise the jaw?

Answer 34

Masseter and temporalis

Question 35

What is the connective tissue that covers individual muscle fibres called?

Answer 35

Endomysium

Question 36

What fixes the origin of the prime mover so that its force is fully directed on the bone on which it inserts called?

Answer 36

Fixator

Question 37

The large, superficial muscle that extends the thigh and rotates the thigh medially at the hip is called what?

Answer 37

Gluteus

Question 38

What kind of nerve transmits impulses to muscle fibres, signalling them to contract?

Answer 38

Motor nerves

Question 39

The tibialis dorsiflexes what?

Answer 39

The foot at the ankle

Question 40

The oricularis oris closes and protrudes what?

Answer 40

The lips

Question 41

What increases the volume of the chest cavity in inspiration?

Answer 41

Diaphragm

Question 42

What is it called when one muscle moves an arm and another muscle undoes the motion?

Answer 42

Antagonistic

Question 43

What surrounds the muscle and merges with the tissues of the tendon?

Answer 43

The fascia

Question 44

What is a voluntary muscle attached to bone called?

Answer 44

Skeletal muscle

Question 45

What stabilizes joints so that undesirable movement does not occur?

Answer 45

Synergist

Question 46

Acetylcholine diffuses across the synaptic cleft and combines with receptors on the surface of the muscle fibre causing what?

Answer 46

Depolarization

Question 47

When muscle cells break down glucose by anaerobic metabolism, what is a waste product?

Answer 47

Lactic acid

Question 48

What are the tough cords of connective tissue that anchor muscles to bones?

Answer 48

Tendons

Question 49

Release of inorganic phosphate from what causes the cross-bridges to flex?

Answer 49

Myosin

Question 50

What extends the forearm at the elbow?

Answer 50

The triceps brachii

Question 51

What is the pattern of transverse bands made up of overlapping muscle filaments called?

Answer 51

Striation

Question 52

Which muscles flex the leg at the knee?

Answer 52

Gastrocnemius

Question 53

When binding sites are exposed, ATP is split and energy is released which energizes what?

Answer 53

Myosin

Question 54

Attachment to a less movable bone is called what?

Answer 54

Origin

Question 55

What do neurotransmitters send signals across?

Answer 55

Synapses

Question 56

What is a threadlike structure that runs lengthwise through the muscle fibre called?

Answer 56

Myofibril